The real thing is sold on another page.
https://miniaturepopup.com/products/miniature-book-kit4
Alice in the Mirror Country [THROUGH THE LOOKING-GLASS] 20x25x6mm 4 books
Simple process just to fold.
The cardboard has already been cut.
Tools to prepare yourself
1. Cutter
2. Tools to attach a folding line
(Naildot pens, ballpoint pens that have stopped appearing, etc.)
3. Stick glue
4. ruler
5. Mat
6. toothpick
7. Pens, etc. (for aging processing)